CALIFORNIA, U.S. - For the first time in 13 years, an asteroid passed so close to our planet.

Avoiding the close call, that could have been a devastating catastrophe for mankind, astronomers said the distance was considered ‘uncomfortably close’ and left even NASA horrified.

If the asteroid hit the Earth, it would have unleashed as much energy as about 1,000 atomic bombs the size of the one dropped on Hiroshima in 1945.

The impact would be able to completely destroy a city the size of London or New York, further causing damage for hundreds of miles.

The Asteroid 2014-JO25, nick-named "The Rock", is a 650-metre asteroid that was closest to Earth on April 19, 2017 at 1.24 pm.

The Rock's orbit took it about 1.8 million km away from Earth - almost four times the distance from Earth to the moon.

It hurtled past at about 73,000mph just over a million miles away.

The asteroid was discovered in May 2014 as part of the Catalina Sky Survey near Tuscon, Ariz.

The survey, which was part of NASA's Center of near-Earth object studies program is aimed at searching asteroids that could be dangerous to Earth.

Reports noted that the asteroid was roughly the size of the Rock of Gibraltar, which is 1,398ft high.

Scientists said that it was a binary asteroid - two rocks that were originally separate bodies.

Many people viewed The Rock from Earth using a small telescope, and will be visible for two days before it vanishes.

Professor Tim Bedding, head of the School of Physics at the University of Sydney said, “If a similar-sized asteroid hits the Earth, it will be catastrophic. If it hit an ocean, Tsunamis will ruin the coastal cities. If it hits land, it will be different scenario, but in both cases he thinks our planet will suffer.”

Further, Brad Tucker, an astronomer at the Australian National University claimed that the Earth will be hit by one of these asteroids, eventually.

Tucker reportedly said, "Our real worry is not something a kilometer long, that's easy to spot. We know where most of these are. Something much smaller, such as the one that exploded over Chelyabinsk in Russia three years ago is more of a threat. That could come out of nowhere. That was about 10 or 20 metres - and that can cause enough damage if it hits the right place. Those we know only a very few percent."

He added, "We are going to have something that hits the Earth eventually. That is inevitable. But the planet has been around for 4.5 billion years and we only know of a few rare instances of very large impacts, so they are not common."

Earlier, in September 2004, Earth had the last close shave with an asteroid when the 3.1-mile wide asteroid Toutatis came within 963,000 miles – just over four lunar distances – of the Earth.